Plate-bar-heating furnace.



2 SHEETS-SHEET 1.

INVENTOR Patented Nbv.30,1909.

famhu QX@ L. C. STEELE.

PLATE BAR HEATING FURNACE.

APPLICATION FILED FEB. s, 1909.

L. c. STEELE;

PLATE BAR HEATING FURNAOB.

APPLICATION rILEnrnB. 8, 1909.

941,738; PatentedN 0,1909.

. 2 8H -SHEET 2.

- -INVENTOR- TED v e rms PATENT OFFICE.

LAWRENCE c. ,s'rnnnn; or VANDERGRIFT, PENNSYLVANIA.

I PLATE-BAR-HEATING FURNACE.

Tb all whom it may concern:

.Be it known that, I, LAWRENCE C. STEE E, a. resident of Vandergrift, in the county of Westmoreland and State of Pennsylvania, have invented a new and useful Improvemerit} "in-Plate-Bar-Heating Furnaces; and 'l' 'do?hereby declare the following to be a full, clear, and exact description thereof.

This invention relates to metal heating furnaces and more especially to furnaces for heating metal blanks. such as plate bars,-

small billets and the like. 7

The object of the invention is to provide a furnace for th'is'purpose in which an absolutely uniform temperature can be'maintainedin all portionsof the heating chamber, and one in which'the bars, etc, are introduced and withdrawn with practically no loss of heat.

My invention comprises the novel features hereinafter set forth andclaimed.

I In the accompanying drawlngsFlgure 1- is a vertical section through lay-improved furnace; Fig. 21s a horizontal section taken on the line 22 Fig. 1, and on line 2 2 Fig. 3 showing portions of the hearth or floor broken away; Fig. 3 is a vertical section on the line Fig. 2; F 1g. 45 is a detail horizontal section showing a slight modification; and Fig. is a section on line Fig. 1.

shaft 8. The chamber walls are also provided with the vestibule 10 by means of which the bars to be heated are introduced and withdrawn. This vestibule forms an inclosure which is'so arranged as 'to prevent the cold air from finding its way to any extent into the furnace during the cha gin-g of the furnace or'the withdrawal of th bars therefrom. To this end the doors 11 d 11 are employed. Said doors are hi ged by suitable hinges l0? to the partit ons- 10 which separate the vestibule from the heating chamber of the furnace. Said vestibule has the top 10 and rear wall 10 These doors l1 and 11 swing freely so that they will be opened by the contact of the bars Specification of Letters Patent. Patented Nov. 30, Application filed February 8, 1909. Serial No. !;?6,78 .t. i

bars have passed. They may beformed of metal lined with asbestos. This vestibule is of sufficient size to admit of a suitable charging device, a cold pair of bars being introduced at the same time a heated pair is ,removed. This apparatus, however, forms no part of my invention.

At the center of the furnace is the mixing and combustion chamber 12, inclosed by the annular bridge wall 13 which projects forwardl some distance above the hearth 5. Communicating centrally with the mixing chamber is the' gas port ll communicating with the gas main 15. In the masonry surrounding the lower part of the mixing chamber 12 is an annular airpassage '16 communicating by means of a series of portal? with said combustion chamber, and'in turn being supplied with air by means of the radially arranged air ports 18 extending through the masonry to the outside of the furnace. The air coming in through these ports enters the combustion chamber through the ports 17 andis there mixed with gas coming through port 1i and is there ignited. The flame passes up over the bridge wall 13, and is drawn outwardly in the form of a mushroom or umbrella to the outlet openings 20 arranged at the periphery ofthe furnace chamber. namely, in the walls 1, and being masonry preferably at a lower plane thanthe air'inletports. 1S. and as the ,masonry becomes heated from these waste gases the air coming through the ports 18- will likewise become heated. The heating effect on the incoming air is very greatly increased by extending the outlet ports radially inwardly as far as possible thus enabling the waste gases to impart most of their heat to the masonry. If desired. the air inlet ports 18 may be arranged parallel with the passages 22, as shown, for instance, in Fig. 4, thus bringing the air passages as close to the waste gas passages as possible, giving the air a high degree of heat.

Flues 26 are formed-in the walls 10 of the vestibule; which communicate with the stackflue to draw or carry off any cold air which may enter when the'doors are opened before said air finds its way into the heating chamber.

In the operation of the furnace the bars 25 will be introduced into the vestibule lO'upon vthe hearth 5, and will be carried by the ter into the heating chamber. In passing from the vestibule into the heating chamber the bars 25 (heated in pairs the one resting on the other) will come into contact with the door 11 and said door will yield and swing back to permit the bars to enter the heating chamber, said door dragging over the top of the bars and preventing the entrance of the air to any extent until said bars have passed beyond the reach of said door whereupon said door drops back to its normal position. At the same time that cold bars are being introduced as above a pair of hot bars having passed through the furnace come;

in contact with the door 11 and said door is opened enough to permit the barsto enter the vestibule in position to be removed therefrom. In this manner the bars are introducd and withdrawn from the furnace with little or no cold air being admitted and the temperaturecan be maintained at an even heat which gives-better and more uniform results.

The air and gas are ignited in the chamber 12, and theflame and heat are drawnover the bridgewall 13 and spread out uniformly, being drawn'through the peripheral out-lets 20, thus givin a uniform and even distri bution of the ame.

What- I claim is:

1. A heating furnace comprising a circular chamber, an air and gas inlet through the center'of the floor of said chamber, a rotating annular hearth in said chamber, and a series of outlet openings atthe periphery of the furnace chamber.

furnace for plate bars com- 2. A" heating prising a circ ar chamber, an endless travelmg hearth therein, aradially arranged vestibule through which the said hearth travels, and doors se arating said vestibule from said furnace c amber.

3. A heating furnace for plate bars, comrising a circular chamber. an endless travel ing hearth therein, a radially arranged vestibule through which the hearth travels, and

travels, a door separating said vestibule fromvsaid heating chamber, and an escape flue formed in the walls of said vestibule adjacentto said door. I

In testimony whereof, I the'said Law- RENCE C. S'rmznn have hereunto set my-hand.

LAWRENCE C. STEELE.

Witnesses:

ROBERT C. TOITEN,

Roar. D. To'rrnN. 

